Operating Instructions for Dynamic Pile Force Readout, Model 2174 (174-1F)

The Model 2174 Dynamic Force Readout is an instrument developed at Texas Transportation Institute for measuring the peak force on the top of piles during driving. The instrument is intended initially for use with piles which have been instrumented with strain gages and ultimately with a universal transducer which can be placed on the head of the pile during driving. Several design features are incorporated to make the instrument particularly useful as a practical field-worthy measuring tool, such as being self-contained and portable with an internal power supply. It uses a carrier type strain gage amplifier and phase sensitive demodulator to suppress self-generating strain gage responses during driving. A special balance error correction amplifier is incorporated to compensate for bridge balance errors (drift) which will be present in any instrumentation on field test piles.